What is y= -x^2-2x+3 in vertex form

           y = -x² - 2x + 3
      y - 3 = -x² - 2x + 3 - 3
      y - 3 = -x² - 2x
 y - 3 - 1 = -x² - 2x - 1
      y - 4 = -(x²) - (2x) - (1)
      y - 4 = -(x² + 2x + 1)
      y - 4 = -(x² + x + x + 1)
      y - 4 = -(x(x) + x(1) + 1(x) + 1(1))
      y - 4 = -(x(x + 1) + 1(x + 1))
      y - 4 = -(x + 1)(x + 1)
      y - 4 = -(x + 1)²
y - 4 + 4 = -(x + 1)² + 4 
           y = -(x + 1)² + 4

16

Step-by-step explanation:

You half the "m" variable, or the one before the "x", then you square it. So it goes like this

= 4, then = 16.

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